NORTHEASTERN FOREST EXPERIMENT STATION 

Upper Darby , Pennsylvania 

No. 73 

1957 " 

V3lue Loss From Weevil-Caused Defects 

In Eastern White Pine Lumber 

Owners of eastern white pine stands suffer financially in several ways from attacks by the white-pine weevil 

(~issodes strobi) . Crooks, forks, and other weevil-caused 

tree-bole deformities increase bucking, logging, and sawing 

costs, and they reduce recoverable vo1umes.l The injuries 

also reduce the average value of the lumber recovered. It 

is only with this reduction in the value of lumber produced 

that this report deals. 

During a recent log-grade study2 at the Pack Dernonstration Forest, Warrensburg, New York, a tally was made of 

the grade yield of lumber produced from 400 logs, many of 

which were ~reeviled.~ A record was kept of the No. 3-, 4-, 

and 5-Common boards in which weevil-caused defects were responsible for degrade. Defects such as cross grain, large 

branch knots, loose knots, red rot ,4 and reaction wood were 

commonly found to be a direct or indirect result of weevil 

injuries. 

Two estimates were then made of the total value of 

the lumber produced from each log. The first was based on 

the actual grades in the lumber tally. The second was made 

by revising the value of weevil-degraded boards, conservatively assuming that each such board would have been graded 

one lumber grade higher if its weevil defect were not present. These two estimates were compared to establish the value of the loss resulting from weevil-caused lumber degrade. 

By relating the number of visible weevil injuries to 

this estimated lumber-value loss per log, a basis is provided for estimating an appropriate reduction in log or tree 

'waters, W.E., McIntyre, T., and Crosby, D. Loss in volume of white pine in 

New Hampshire caused by white pine weevil. Jour. Forestry 53: 271-274. 1955. 

 onsor so red jointly by the College of Forestry, State University of New York, 

and the Northeastern Forest Experiment Station, U. S. Forest Service. For further details of the1 study see Northeast. Forest Expt. Sta. Forest Res. Notes 67 

and 68, 195 7. 

'ln this report, 'weevil injury9 refers to all weevil and revil-like injuries observed, although some of these may have been caused by birds, squirrels, or other insects. 

40strander, M. D., and Foster, C. H. Weevil-red rot association in eastern white pine. Northeast. Forest Bpt. Sta. Forest Res. Note 68. 2 pp. 1957. 
value prior to sawing (table 1). In this study, 80 percent 

of the actual weevil injuries were detected by surface defects on the logs. 

Care must be used in drawing conclusions from these 

data because all of the logs are from one locality. And 

although they came from trees 45 to 120 years old, none was 

from severely deformed trees. Data now being collected will 

strengthen the sample, but certain conclusions already seem 

justified. 

Table 1.--Reduction in lumber value due to weevil-caused defects 

'*~ased on wholesale lumber prices, as quoted in ~ommercial~ulletin, 

1953-56. +st From weevil injuries undetected on the log surface. 

The most obvious conclusion is that reduction in lumber quality from weevil-caused defects is substantial, 

Losses in lumber value of $10 per thousand board feet (two 

to three weevilings per log) reduce log or stumpage conversion values at least a like amount. In stands where stumpage 

is selling for $25 per thousand board feet, a potential loss 

or gain of $10 per thousand is of great significance. 

Observed 

weevil injuries 

(NO. per log) 

A tentative guide to part of the effect on log and 

tree conversion value of weevil damage is provided by these 

data. In general, the first observed weevil injury in each 

log means that its value can be reduced about $5 per thousand board feet below that of logs in which no evidence of 

weeviling is seen; each successive injury further decreases 

the value by about $2 per thousand board feet. These conservative loss estimates are in addition to volume losses 

and other forms of weevil-caused losses. 

No. Bd.ft. 

0 $130 $9 190 13,221 

1 109 7 107 6,256 

2 109 9 42 1,870 

3 104 11 30 1,411 

4 108 13 11 416 

5 106 14 4 132 

6 125 34 2 49 

Basis 

--MYRON D. OSTRANDER and CARL H. STOLTELTBERG 

Potential 

lumber valueii 

per M bd.ft. Logs 

Forest Economists 

Northeastern Forest Experiment Station 

Forest Service, U.S. Dept. Agriculture 

Weevil-caused 

reduction in 

lumber value 

per M bd.ft. 

Lumber 

tally 

Agricul ture-Fores t Service-Upper Darby